Double three-roller drawing frame



Feb. 22, 1938. H. STROINK 2,103,930

DOUBLE THREE-ROLLER DRAWING FRAME Filed Feb. 6, 1935 2 Sheets-Sheet l 9 FJ' 9.1a

Fig.1 2 O lnvenfor:

Feb. 22, 1938. H. STROINK 2,108,930

DOUBLE THREE-ROLLER DRAWING FRAME Filed Feb. 6, 1935 2 Sheets-Sheet 2 Ia/anion ff Sa /"0 in if Patented F eb. 22, 1938 UNITED STATES PATENT OFFICE Baumwollspinnerei many Gronau,

Gronau, Ger- Application February 6, 1935, Serial No. 5,294

In Germany August 30, 1934 2 Claims.

This invention relates to a double three roller drawing frame.

In three cylinder cotton spinning double roller drawing frames are employed, in which the middle one of the three lines of drawing rollers carriestwo press rollers of which the rear'one is the feed or preliminary draft roller and, owing to its own weight or special weighting, heavier than the front drawing roller positioned nearest the front cylinder nip and at the initial nip of the main area of draft. These two press rollers are in known constructions either not adjustable or they can be adjusted only in dependence upon each other and together with the central lower cylinder on which they rest. Other constructions are known which afford an opportunity of adjusting the light drawing roller from the stationary stand.

It has been found in practical operation that the arrangement of the light, i. e., drawing, roller relative to the front cylinder nip and the central lower cylinder is of decisive importance for the uniformity and degree of draft as well as for the quality of the yarn. If this drawing roller is located too far in. front, i. e., towards the front cylinder nip, the pressure on the lower cylinder will be slight, and it might happen that it will be driven only intermittently by the lower cylinder and the interposed sliver and even stop when laps due to dust form at the pivots. This trouble appears also when the drawing cylinder, owing to inaccuracies in the construction of the drawing frame, is not positioned parallel to the lower cylinder by which it is supported.

The invention proposes to eliminate these defects by rendering the light drawing roller located at the initial nip of the main field of draft adjustable from the adjustable cover of the stand, independently of the preliminary draft, front and middle cylinders.

One form of the invention is illustrated in the accompanying drawings, in which Figures 1 to 5 are detail views of the means employed to attain the object of the invention.

Fig. 6 is a side elevation with parts in section of the double three roller drawing frame.

Referring to the drawings, in the bearing point of the drawing roller a forked adjusting slide 1 of plate steel or other suitable material, as shown in Figs. 4 and 5, is inserted beyond the cap bar 5, Fig. 4, in such a way that the slide 1 is bent down the sides of the cap bar nep 6 and forms an oblique edge towards the pivot I 6 of the drawing roller, so that it must move with this edge acting as abutment. The cap bar nep 6 is secured to the cap bar 5 by the bolt 8.

' The adjusting slide I is secured to the cap bar nep by means of the screw 9 and a washer, as indicatedin Figs. 1, 4, and 5, so that it can be moved to and fro in a slot of the slide and then screwed into position.

With the adjusting slide cooperates a drawing cylinder 2 whose pivots, in contradistinction to other constructions, are as short as possible, as

shown in Fig. 3, and connect with the cylindrical portion of the roller in the form of a neck portion and, furthermore, form a hemisphere, paraboloid or half an ellipsoid in the direction of the longest diameter. Practical experiments have shown that cylindrically reduced or conical pivots are not satisfactory, since they promote the accumulation of dust and the formation of laps. The words "neck portion of the pivots as used herein is that portion of the cylinder between the pivot proper and the cylindrical part of the drawing cylinder which prevents contact between the side and thecylindrical portion.

The neck portion ll serves to keep the side faces of the press rollers free from the side faces of the adjusting slides, so that they are not impeded in rotation and, moreover, can automatically adjust themselves between the bearing edges of the adjusting plates parallel to the lower cylinder.

Owing to this arrangement, the drawing cylinders are brought into a position relative to the lower cylinder, which is most favorable to the draft process and in which they are continually rotated by the middle cylinder, since the use of .the pivots described having a curved surface and of the upright edges of the adjusting slides for the cylinder insures the formation of a point bearing by means of which pivot friction is reduced to a minimum and can be easily overcome. The drawing cylinders may, further, with or without the front press cylinders, be brought into a position most favorable for the quality of the yarn without causing any change in the position of the preliminary draft cylinders relative to the central lower cylinder and thus of their pressure on the lower cylinder. On account of the peculiar shape of the curved short pivots connecting with their drawing cylinder by means of a neck portion, no dust can accumulate thereon. Furthermore, the cooperation of these pivots with the upright edges of the side bearings causes the drawing cylinder automatically to adjust itself in its travel parallel to the lower cylinder and to be driven thereby so as to insure uniform rotation.

I claim:-

1. In double three roller drawing frames with upper and lower drawing cylinders, bearings for said drawing cylinders, a carrier cylinder having pivots extending a relatively short distance from the ends thereof, said pivots being of curved convex outline and increasing in cross section towards the cylindrical part of said carrier cylinder and a neck portion connecting said pivots tothe cylindrical part oi the carrier cylinder, an adjustable cap bar carried on said frame, steel plate adjusting slides screwed on said adjustable cap bar and engaging like riders the bearing points of said pivots so that the adjusting slides form at their upright edges abutments for the curved pivots of said carrier cylinder by producing pointlike bearings.

2. In double three roller drawing frames with upper and lower drawing cylinders, bearings for said drawing cylinders, a carrier cylinder having pivots extending a relatively short distance from like bearings.

HERBERT B'I'ROINK. 

